Fix dither artifacting errors in certain image formats

Author: JosipKuci

src/graphics/ImageColor/ImageColor.cpp

@@ -25,13 +25,12 @@
 ImageColor *_imagePtrJpeg = nullptr;
 ImageColor *_imagePtrPng = nullptr;
 
-// uint8_t (*ImageColor::ditherBuffer)[E_INK_WIDTH + 20] = nullptr;
+#if defined(ARDUINO_INKPLATE2) || defined(ARDUINO_ESP32S3_DEV)
 __attribute__((section(".ext_ram.bss"))) int16_t ImageColor::ditherBuffer[3][8][E_INK_HEIGHT];
+# else
+__attribute__((section(".ext_ram.bss"))) int16_t ImageColor::ditherBuffer[3][8][E_INK_WIDTH+200];
+#endif
 
-// int16_t (*ImageColor::ditherBuffer)[8][E_INK_WIDTH + 20] = nullptr;
-// uint8_t *ImageColor::pixelBuffer = nullptr;
-// uint32_t *ImageColor::ditherPalette = nullptr;
-// uint8_t *ImageColor::palette = nullptr;
 
 void ImageColor::begin(Inkplate *inkplateptr)
 {

src/graphics/ImageColor/ImageColor.h

@@ -110,18 +110,21 @@ class ImageColor
     void getPointsForPosition(const Position &position, const uint16_t imageWidth, const uint16_t imageHeight,
                               const uint16_t screenWidth, const uint16_t screenHeight, uint16_t *posX, uint16_t *posY);
     uint8_t findClosestPalette(int16_t r, int16_t g, int16_t b);
-
-
-  private:
+    
 #if defined(ARDUINO_INKPLATE2) || defined(ARDUINO_ESP32S3_DEV)
     uint8_t pixelBuffer[E_INK_HEIGHT * 4 + 5];
+    static int16_t ditherBuffer[3][8][E_INK_HEIGHT];
+    static const unsigned int width = E_INK_HEIGHT, height = E_INK_WIDTH;
 #else
     uint8_t pixelBuffer[E_INK_WIDTH * 4 + 5];
+    static int16_t ditherBuffer[3][8][E_INK_WIDTH + 200];
+    static const unsigned int width = E_INK_WIDTH, height = E_INK_HEIGHT;
 #endif
-    static uint8_t (*jpegDitherBuffer)[18];
-    // static int16_t (*ditherBuffer)[8][E_INK_WIDTH + 20];
-    static int16_t ditherBuffer[3][8][E_INK_WIDTH + 20];
 
+
+  private:
+
+    
     uint32_t ditherPalette[256]; // 8 bit colors, in color, 3x8 bit colors
     uint8_t palette[128];        // 2 3 bit colors per byte, _###_###
 

src/graphics/ImageColor/ImageDitherColor.cpp

@@ -22,29 +22,6 @@
 
 extern ImageColor *_imagePtrJpeg;
 
-
-#if defined(ARDUINO_INKPLATECOLOR)
-
-static uint32_t pallete[] = {0x000000, 0xFFFFFF, 0x00FF00, 0x0000FF, 0xFF0000, 0xFFFF00, 0xFF8000};
-static unsigned int width = E_INK_WIDTH, height = E_INK_HEIGHT;
-
-#elif defined(ARDUINO_INKPLATE2)
-
-static uint32_t pallete[] = {0xFFFFFF, 0x000000, 0xFF0000};
-static unsigned int width = E_INK_HEIGHT, height = E_INK_WIDTH;
-
-#elif defined(ARDUINO_INKPLATE4) || defined(ARDUINO_INKPLATE7)
-
-static uint32_t pallete[] = {0xFFFFFF, 0x0000000, 0xFF0000};
-static unsigned int width = E_INK_WIDTH, height = E_INK_HEIGHT;
-
-#elif defined(ARDUINO_ESP32S3_DEV)
-//static uint32_t pallete[] = { 0x424852, 0xA1A8A8, 0xB0AB44, 0x7D4749, 0x4B689A, 0x516A64};
-static uint32_t pallete[] = { 0x000000, 0xFFFFFF, 0xFFFF00, 0xFF0000, 0x0000FF, 0x00FF00};
-static unsigned int width = E_INK_WIDTH, height = E_INK_HEIGHT;
-
-#endif
-
 /**
  * @brief       findClosestPalette return closes pallete for given pixel
  *
@@ -117,12 +94,9 @@ uint8_t ImageColor::ditherGetPixelBmp(uint32_t px, int i, int j, int w, bool pal
     int16_t g = GREEN8(px) + ditherBuffer[1][j % 8][i];
     int16_t b = BLUE8(px) + ditherBuffer[2][j % 8][i];
 
-    if (i == w - 1) {
-        int row = j % 8;
-        memset(ditherBuffer[0][row], 0, w * sizeof(int16_t));
-        memset(ditherBuffer[1][row], 0, w * sizeof(int16_t));
-        memset(ditherBuffer[2][row], 0, w * sizeof(int16_t));
-    }
+    ditherBuffer[0][j % 8][i] = 0;
+    ditherBuffer[1][j % 8][i] = 0;
+    ditherBuffer[2][j % 8][i] = 0;
 
     r = max((int16_t)0, min((int16_t)255, r));
     g = max((int16_t)0, min((int16_t)255, g));

src/graphics/ImageColor/jpegHelpers/ImageJPEG.cpp

@@ -377,12 +377,12 @@ bool ImageColor::drawJpegChunk(int16_t x, int16_t y, uint16_t w, uint16_t h, uin
 
     // Carry global error from previous scanline
     if (dither && y != _imagePtrJpeg->lastY)
-{
-    // We moved to a new scanline
-    int oldRow = _imagePtrJpeg->lastY & (18 - 1);
+    {
 
-    _imagePtrJpeg->lastY = y;
-}
+        _imagePtrJpeg->lastY = y;
+    }
+
+    unsigned int width = _imagePtrJpeg->width;
 
 
     // --- Draw the JPEG MCU block ---
@@ -403,7 +403,7 @@ bool ImageColor::drawJpegChunk(int16_t x, int16_t y, uint16_t w, uint16_t h, uin
             if (dither)
             {
                 val = _imagePtrJpeg->ditherGetPixelBmp(((uint32_t)r << 16) | ((uint32_t)g << 8) | ((uint32_t)b), i + x,
-                                                       j + y, E_INK_HEIGHT, 0); // Changed from E_INK_WIDTH
+                                                       j + y, width, 0);
             }
             else
             {

src/graphics/ImageColor/pngHelpers/ImagePNG.cpp

@@ -58,6 +58,8 @@ void pngle_on_draw(pngle_t *pngle, uint32_t x, uint32_t y, uint32_t w, uint32_t
         _pngPosition = ImageColor::_npos;
     }
     if (rgba[3])
+    {
+    unsigned int width = _imagePtrPng->width;
         for (int j = 0; j < h; ++j)
             for (int i = 0; i < w; ++i)
             {
@@ -81,7 +83,7 @@ void pngle_on_draw(pngle_t *pngle, uint32_t x, uint32_t y, uint32_t w, uint32_t
 
                 if (_pngDither)
                 {
-                    px = _imagePtrPng->ditherGetPixelBmp((r << 16) | (g << 8) | (b), x + i, y + j, pngle_get_width(pngle), 0); // Changed from e_ink_width
+                    px = _imagePtrPng->ditherGetPixelBmp((r << 16) | (g << 8) | (b), x + i, y + j, width, 0); // Changed from e_ink_width
                 }
                 else
                 {
@@ -90,6 +92,7 @@ void pngle_on_draw(pngle_t *pngle, uint32_t x, uint32_t y, uint32_t w, uint32_t
                 }
                 _imagePtrPng->_inkplate->drawPixel(_pngX + x + i, _pngY + y + j, px);
             }
+    }
 
     if (lastY != y)
     {